Gunsight with visual range indication

ABSTRACT

A laser beam generating module capable of projecting a series of concentric circles of light is connected to the frame of a firearm in substantial alignment with the gun barrel. The laser beam can be actuated on demand, and the resultant pattern will be projected onto the target. Due to the intrinsic fan angle of the spatially projected beams, the circles displayed on the target will appear to be spaced further apart when the target is further away, and appear to be spaced closer when the target is nearer. By selecting a suitable laser fan angle, it is possible to get an immediate visual indication of the approximate range to the target increasing the potential accuracy.

This application is a U.S. Patent Application that relies for priorityunder 35 U.S.C. 120 on Provisional Application Ser. No. 61/432,934 filedon Jan. 14, 2011, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to weapons systems, and moreparticularly to firearms which include means for generating a laser beamas an aiming mechanism. It is well known in the firearms art to connecta means for generating a laser beam aligned to the barrel axis of thefirearm as an aid to aiming the weapon to deliver a projectilesubstantially at the point where the laser beam intersects the target.

2. Statement of the Prior Art

Among law enforcement officers, these laser aiming devices are highlyprized. Confrontations requiring the use of firearms rarely occur inbroad daylight. Most police work which requires firearms occurs in poorlighting conditions, either indoors or outside. These poor lightingconditions make it difficult to use conventional optical gun sightseffectively. Use of a laser aiming device requires the officer to merelypoint the firearm at the target so that a bright laser dot is projectedonto the target. The intimidating effect on the violator on seeing thelaser dot on his person is often sufficient to cause them to capitulateand reduce the potential for violence.

Prior art laser aiming devices often project a single laser beam or, ina few instances, a circle and a dot or a crosshair. This laser beam isusually red, but newer devices also use green lasers as these appearbrighter to the eye. Means is provided to actuate the laser on demand,usually by a trigger switch, to avoid alerting the target to thelocation of the firearm, and also to conserve battery power. Means isalso provided to align the laser to the firearm barrel axis.

The major drawback of prior art laser aiming devices is due to the factthat only a single laser beam is projected. A dot, usually red, willappear on the target at the point where the projectile will impact. Thisdot is the same size over a wide range of distance from the firearm tothe target. In certain prior art, a circle or crosshair may be projectedas a means to providing an indication of a supposed “splatter zone”based on the MOA (i.e., Minute of Angle or Minute of Arc).

As is well known, MOA is a unit of angular measurement used in thefirearms industry on scopes or firearms to define shooting accuracy. Itis popular because 1 MOA almost equals one inch (1.0472 inches to bemore precise) at 100 yards. However, the person operating the firearmhas no means of determining the range to the target. This is important,especially with handguns, where the firearm accuracy deterioratesrapidly with distance. Furthermore, poor lighting conditions and theheat of combat often make it difficult to see the small projected laserdot. Valuable seconds may be lost trying to determine exactly where thegun is pointing. Certain prior art laser aiming devices use a camerawith a range finder to display the distance to the target. However, thisis impractical for handgun use where a rapid response is essential.

Most confrontations with law enforcement occur at fairly close range(e.g., 10 to 30 feet). In many cases, the law enforcement officer needsto rapidly deploy his weapon and all he has time for is to point theweapon at the assailant. While laser-pointer type aiming devices arevery useful in this “point and shoot” situation, they provide no meansfor the officer to judge distance to the target, and thus the relativeaccuracy of his shot. This is particularly difficult in poor lightingconditions where human depth perception is severely compromised.Obviously, in the aforementioned situation there is no time for theofficer to use a conventional optical rangefinder to determine thedistance to the target.

What is needed is a laser aiming device that combines the ease of use ofa laser pointer gun sight with additional visual indication of range.Such a laser aiming device needs to work at relatively short ranges of10 to 50 feet and not require substantial time to interpret. It shouldalso be easily retrofitted to existing firearms and require minimaltraining.

SUMMARY OF THE INVENTION

These and other objects, advantages, and novel features are provided byembodiments of the present invention, which overcome all thesedifficulties and provides all the desired features by projecting aspatial laser light pattern comprising a series of concentric, closedplane shapes instead of a single beam. The projected spatial laser lightpattern may be designed with a specific fan angle so that the projectionappears bigger, the further away it is projected. With a projectedspatial laser light pattern comprising concentric, closed plane shapes,the closed plane shapes will appear to be smaller and spaced closertogether at short distances, and will appear wider and spaced furtherapart at longer distances. By the visual appearance of the projectedspatial laser light pattern, the firearm user can instantly determinethe approximate distance to the target and thus improve the potentialaccuracy of the shot.

The series of concentric, closed plane shapes may comprise circles,ellipses, or quadrilaterals such as rectangles and squares, orcombinations thereof (e.g., a series of concentric circles and squaresor a series of concentric ellipses and rectangles). For significantlyimproved depth perception, embodiments of the present invention maycomprise a series (e.g., 3 or more) concentric circles to be projected.This, in effect, channels the shooter's eye to the center of the target.Projection of these circles, while superficially resembling a2-dimensional bull's eye, is really perceived as a visual tunnel. Forexample, at a short distance to the target, the projected image on thetarget will be a series of very closely spaced circles, where theoutermost circle will be small. But, if the target is further away, thenthe circles will be spaced further apart and the outermost circle willappear larger, giving an instantaneous visual cue as to the relativedistance of the target from the shooter. This depiction subconsciouslycues the shooter as to the approximate distance to the target, perhapsby producing the illusion of a narrow (i.e., short) tunnel, or of a wide(i.e., long) tunnel. A center dot may be provided as an aid for aimingthe firearm towards the exact center of the tunnel. The center dot is amatter of preference and not essential in itself to the invention.

Furthermore, in a stressful low light confrontation, the spatial laserlight pattern of concentric circles enables the operator of the firearmto acquire the target much faster than prior art single dot laserpointer gun sights, potentially giving the shooter a tactical advantage.

The fan angle of the spatial laser light pattern of concentric circlesmay also be adjusted to match the shot spread pattern of specificfirearms.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present invention will becomemore apparent from the following description of exemplary embodiments,as illustrated in the accompanying drawings wherein:

FIG. 1 is a perspective view of an aiming device mounted on a firearm toproject a spatial laser light pattern onto a target in accordance withone embodiment of the present invention;

FIG. 2 is schematic view of the various components of the aiming deviceshown in FIG. 1;

FIG. 3 is front view of projected spatial laser light patterns that maybe used with the aiming device shown in FIG. 1; and

FIG. 4 is a side view of an illustrative projected spatial laser lightpattern at various distances from the firearm.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments are discussed in detail below. While specificexemplary embodiments are discussed, it should be understood that thisis done for illustration purposes only. In describing and illustratingthe exemplary embodiments, specific terminology is employed for the sakeof clarity. However, the embodiments are not intended to be limited tothe specific terminology so selected. Persons of ordinary skill in therelevant art will recognize that other components and configurations maybe used without departing from the true spirit and scope of theembodiments. It is to be understood that each specific element includesall technical equivalents that operate in a similar manner to accomplisha similar purpose. Therefore, the examples and embodiments describedherein are non-limiting examples.

Referring now to the drawings, wherein like reference numbers generallyindicate identical, functionally similar, and/or structurally similarelements, there is shown in FIG. 1 an aiming device 10 according to oneembodiment of the present invention.

Aiming device 10 may, as shown in FIG. 1, comprise a laser gun sight forinstallation on a firearm 12, typically a handgun. However, it may alsocomprise a sight for use on a shotgun, rifle, or archery bow. Itgenerally comprises a module capable of projecting a spatial laser lightpattern, means for mounting the laser module in substantial axialalignment with the barrel of the firearm 12, a power source, and aswitch to actuate the module.

In this embodiment, the laser module is adapted to be attached to amounting means such as a Picatinny rail 19 that is affixed to the barrel18. The Picatinny rail 19 (also known as a MIL-STD-1913 rail or STANAG2324 rail or a “Tactical Rail”) is a bracket used on some firearms inorder to provide a standardized mounting platform. It facilitates quickmounting of the laser module without requiring realignment. Use of aPicatinny rail facilitates moving the device to different firearms,though any suitable method of attaching the module in substantial axialalignment to the firearm barrel is acceptable. A similar system is theWeaver rail, which uses a pair of parallel rails and several slotsperpendicular to such rails.

One difference between the Picatinny rail and the Weaver rail is thesize of these slots, although many rail-grabber-mounted accessories canbe used on either type of rail. Weaver rails have a slot width of 0.180in (4.572 mm), but are not necessarily consistent in the spacing of slotcenters. The Picatinny locking slot width is 0.206 in. (5.232 mm) andthe spacing of slot centers is 0.394 in. (10.008 mm). Because of this,with devices that use only one locking slot, Weaver devices will fit onPicatinny rails, but Picatinny devices will not always fit on Weaverrails. The other difference is that Weaver rails are continuous, whilePicatinny rails are cut by the slots (i.e., like a dotted line) toneutralize expansion caused by barrel heating.

An actuation means or switch 14 is mounted on the side of the hand grip16 so that the laser can be actuated by side pressure of the triggerfinger. This is a common setup used with conventional single beam lasergun sights. Switch 14 can be mounted on either side to accommodate leftor right handed users. Other means of actuation, such as tilt sensors ortrigger mounted switches could also be used. The power source or battery20 may be mounted in the rear of the laser module 10, although it couldeasily be placed elsewhere on the firearm 12. When the laser is actuatedusing switch 14, a spatial laser light pattern is projected. Theprojection 24 can be seen on the target 26. In this embodiment, theprojected pattern is a series of concentric circles with a center dot.If the target is further away, as depicted by 28, then only a portion ofthe pattern 25 is seen on the target indicating to the user that thetarget is further away and accuracy of the resultant shot would begreatly reduced. The large size of the projection ensures that it iseasy to quickly locate the aiming point in a combat or law enforcementsituation. The large projected image onto the target is also is adeterrent to violence as the target can see that he/she is well withinlethal range of the firearm and should surrender peacefully.

FIG. 2 shows a detail of the laser gun sight. Laser pattern generator 30suitably comprises a Lasiris™ SNF, Model 507C, which projects 7concentric circles and is manufactured by Coherent Inc. of Montreal,Canada. It contains a laser diode 32, a diffraction grating 34, and afocusing lens 36 to generate a focused projected laser pattern. Thelaser diode 32 has a power output of about 10 mW, which has been foundto be satisfactory for a desired projection distance of up to 50 feet inboth indoor and low light conditions. Modules with higher output power(up to 200 mW) are available if more range is needed, or if the deviceis intended for use in broad daylight.

The diffraction grating 34 generates the desired spatial light pattern.Many patterns are possible as shown in FIG. 3, including rectangulargrids and dot matrices. Other custom designs can be produced by simplychanging the diffraction grating. In the preferred embodiment,diffraction grating 34 was selected to generate a pattern of 7concentric circles plus a center dot. This has been found to be apresently preferred embodiment of the invention. The concentric circlepattern provides instant feedback of depth perception and with a fewhours of training users can judge the distance to the target by justflashing the concentric circle projection. The concentric circles arealso intuitive as they superficially resemble a bull's eye target thatis familiar to all shooters. The center dot provides an aim pointconsistent with existing single dot laser gun sights, thus facilitatingthe transition from conventional single dot laser point type gun sights.Lens 36 can be adjusted to focus a sharp image of the concentric circlesat the desired range. In one embodiment, this was set to be in focusfrom 10 to 30 feet.

In the preferred embodiment, a red laser (i.e., 635 nm wavelength) wasused. A green laser (i.e., 532 nm wavelength) would be even better asthe human eye perceives higher brightness at the lower wavelength forthe same laser power output.

FIG. 4 shows how the beam diverges with distance from the laser gunsight. In the preferred embodiment, the fan angle 40 was 1 degree. Withthis fan angle, the innermost circle appears to be about 2 inches wideat position 42 (i.e., a distance of about 10 feet) and the spacingbetween the concentric circles or“intercircle spacing” is about 1.5inches. Again, with a 1 degree fan angle, the innermost circle appearsto be about 5.5 inches wide at position 44 (i.e., a distance of about 20feet) with an intercircle spacing 41 of about 2 inches. Finally, with a1 degree fan angle, the innermost circle appears to be about 8.3 incheswide at position 46 (i.e., a distance of about 30 feet) with anintercircle spacing of about 4.3 inches. So, with this selected fanangle of 1 degree, the visual range of the sight is from about 5 to 30feet. This roughly corresponds to the practical useful range of ahandgun under real world conditions. Other fan angles (e.g., from about0.1 to about 2 degrees) can be selected to adjust the sight to longerranges.

It is, thus, possible for the user to estimate the distance to thetarget from the apparent size and intercircle spacing of the projectedspatial laser light pattern onto the target. With minimal training thisperception of distance becomes intuitive and is performedsubconsciously. This distance estimation technique based on the apparentsize and intercircle spacing of the projected pattern worksexceptionally well in poor lighting conditions where the human eye isnot capable of significant depth perception due to lack of visual cues.

In the preferred embodiment, the interbeam angle between circles was0.77 degrees. This affects the spread of the concentric circles aroundthe innermost circle. This coupled with the fan angle can be used toadjust the projected pattern of circles for different overall size ofthe projected circles as well as the intercircle spacing.

While the disclosure has been described with reference to severalembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the disclosure. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the disclosure without departing fromthe essential scope thereof. Therefore, it is intended that thedisclosure not be limited to the particular embodiments disclosed as thebest mode contemplated for caring out this disclosure.

What is claimed is:
 1. A weapon system, comprising: a weapon; and alaser module for aiming said weapon, wherein said laser module ismounted on said weapon and adapted to project a spatial laser lightpattern on a target that provides a user of the weapon system a visualindication of range to the target; wherein said spatial laser lightpattern is projected at a predetermined fan angle and wherein saidpredetermined fan angle comprises from about 0.1 to about 2 degrees. 2.The weapon system according to claim 1, wherein said predetermined fanangle comprises 1 degree.
 3. A weapon system, comprising: a weapon; anda laser module for aiming said weapon, wherein said laser module ismounted on said weapon and adapted to project a spatial laser lightpattern on a target that provides a user of the weapon system a visualindication of range to the target, and wherein said laser module furthercomprises: a laser diode; a diffraction grating; and a focusing lens togenerate a focused spatial laser light pattern.
 4. The weapon systemaccording to claim 3, wherein said laser diode comprises a red laserdiode.
 5. The weapon system according to claim 3, wherein said laserdiode comprises a green laser diode.
 6. The weapon system according toclaim 3, wherein said focusing lens is adapted to generate a focusedspatial laser light pattern at a distance of up to about 100 feet.